1. Field of the Invention:
This invention relates to a fuel cut system for an electronic control engine.
2. Description of the Prior Art:
When the deceleration of engine rotation is large and the rotational speed of the engine in which the fuel cut is completed is low, the rotational speed of the engine is rapidly reduced even after the resumption of fuel supply, resulting in the engine stop. Corrective measures contemplated to avoid such a situation are enumerated as follows;
(1) When the fuel cut is carried out with 7 km/h or less vehicle speed as in the case of racing, the rotational speed of the engine in which the fuel cut is completed is set to a large value. PA0 (2) When a clutch is released as in the case of a transmission under the neutral condition, the fuel cut is stopped. PA0 (3) When the deceleration of engine rotation is larger asynchronous fuel injection is carried out in the resumption of fuel supply.
In the first and second corrective measures, fuel cut time is reduced and rate of fuel consumption cannot be sufficiently improved. In the second corrective measure, a detector and wiring for detecting the released condition of clutch are needed so that the constitution is complicated. In the third corrective measure, the rotational speed of the engine is temporarily lower than idling rotational speed even after the resumption of fuel supply so that third corrective measure cannot sufficiently avoid the engine stop.